Honestly, I think they look pretty good.
I would recommend getting your elbows a little more down and out in the rack position. It'll help with the push under and keeping a very tight back, particularly the upper area. I also recommend you smooth that dip out. If you rush that dip, you'll become disconnected from the bar, which will eventually lead to miss lifts (unless you're ridiculously strong and can withstand a heavy barbell crashing onto you).
You can also do some tall jerks to work on the speed pushing under the bar. If you want, you can try moving your feet as well to see if that helps your speed any.
Hope this helps,
Javier A. Sanjuan
Olympus Barbell Club
Dear God, please help me lift heavy and be awesome. Thanks. Amen.